Lifting device for pallets or the like



Jan. 17, 1950 H. MADSEN LIFTING DEVICE FOR PALLETS 0R THE LIKE Filed July 19, 1948 IN VEN TOR. HowardMmZsm A TroR/v E Y Patented Jan. 17, 1950 LIFTING DEVICE FOR PALLETS OR THE LIKE Howard Madsem San `ilranciscm. Calita Application July19, 1948;. Serial No..39;537

(Cl.r29482) 11.`Glaims.

The present invention relates to improvements'* infalifting device for pallets or Vthe like, prin` cipallyintended for use in connection with shiploading operations.`

Pallets of this `character usually consist of two layers of planks secured upon interposed spacing` blocks. The articles to be loaded are stacked uponthe-pallets andthe .latter `are then `lifted and"transported` by suitablecranesnr other hoistingmachinery` The `bottom layerofplanks usually rests `on a;

suitable supporting surface,` and Lthemost `convenient `waygof4 gripping the 4palletior hoisting operations isbylmeans `of a bar `introduced sidewise between` the twoA layers intermediate the spacing blocks.

Upward pull `ongthsbar is necessarily applied outside thepalleta and if such 'upward` pull is.

exerted by meansyof "a hoisting .cable, theloar` tends to slant away fromthebottom face of the upper layerfwith the resultthat theliitingwefect plankand Athat the `bar tends to slip away` froml underneath the upperlayer of planks.

In thepresent invention itis proposed to pro?` Videa lifting mechanism in `connection with the. said bari which `utilizes `the lifting eiort `for forcing the full length. of the `barirlto ,lifting contact4 withvthe upper layerof. planks so that the load is `uniformly distributed overj the full length oi the bar and any dangerof slipping yis. eliminated.

Pallets of this character `are usually` rectan` guiar in form, and. when the. articleal such as boxes Vor cartons, are stacked `on the pallet,.they are usually made to rise vertically from `the edges ofthe 'palletsothat the entire verticalljspace above the `pallet `is occupied :by the merchandiseM tobe stored andthere is no room in said "space` for `the accommodation of any part of the.1ift.

ing mechanism.` p

tisytherefore, further proposed in the present invention to arrange the lifting mechanism in.`

L While I haver shown onlyL the preferred forni of-my*inventionl Irwish to have itundlerstood` that various Ecl'langesvand `modifications may .bei made within the yscope 4of the claims` attachediz hereto without 'departing from` the spirit of thef *l invention.

lteferringto` the drawing` in detail,` a portionq of the'pal'letel iisshownfin dotted lines as com` prising la i lower layer f of` i planks 2 arranged iin:

slightly `spaced relation, a` series of `spacingiblocks 3""superimposed on theiplanks transversely, in widely spaced relatiom and fan `upper layer of planks Il` superimposedon `thefspacing` blocks to` registervwith'the 'lower planks. Thefplanks `are usually made of two inch material and the spacing'blocks of A`4-x fls, and allthe members are securely fastened to oneanother to forma rec` tangularloadinggplatform. As arule three spac.`` ingblocks are employed, leaving `two intermediate spaces for-'accommodationof` `my lifting devices, of which fourarenormally applied, two for each side.A The viourliftingdevices are adapted for connectiontoa common hoist by means of cables or the like.

Onlyone'of the lifting devices'is illustrated inithe drawing and it comprises in its principal features` a bar 5 adapted for introduction from the sideinto one of thespaces provided between thejspacing blocks, a `bell crankllever E to which the bar is anchored nas at l, a `link t pivotedto the "extreme outer `endfoi' the bar, and `a `lever mechanisrn";9j"operative on the link 8 for urging the inner 1'end of the `bar upward in response to` arr upwardpull exerted on the lever mechanism;

The bar` 5 :is Jpreferably made in the formof aninvertedchannel and is of suicient lengthito allowrits inner'end` In toprojectinto the pallet for aconsidera'ole distance, while `its outer `end l l` projects outside the pallet.

The bar is pivotally supported nearfitsouter endbetween two spacedsections of the bellcrank lever 6; each section `comprising a horizontal leg I2 running-fsubstantially*parallel to the bar andl averti'cal` leg i3 lrisingvertically therefrom,and the twosections, being. connected to form a rigid unit, bylmeansMacross-member i4. The pivot 'I fislocated in thegelbow of the lever, and the horizontal sections of `thebell crank lever are made to straddle thelcar.`

The bar and the horizontal legs of the 'lever are free to` swing with respect to lone another on thepivotl, but'sinceonly arelatively. slight amount"of""play is necessaryforjthe operation of .my` lifting device, I limit the play by meanslof a1 bolt l5" whichpasses through the horizontal leg'ofthe lever and the bar, near the end of the former, one of the said members being slotted as at I6 to provide for the necessary freedom of play.

The two vertical legs I3 of the lever 6 have arms I1 projecting outwardly therefrom in a downwardly inclined direction, these arms carrying, on a pivot pin I8, a pinion I9 adapted for meshing engagement with a rack 20 formed upon the rear face of the link 8, the latter being urged upon the pinion by a pair of springs 2| connecting a rod 22 extending transversely through the upper end of the link to the two upright lever legs.

The pinion I9 has two arms 23 projecting downwardly therefrom in an inclined direction and toward the upright lever legs I3, the arms being formed rigid with the pinion, and the outer ends of the arms being connected by a pin 24 adapted to engage over a loop 25 of a cable 26. The pin 24 is located approximately along the outer edges of the upright lever legs I3, and the cable is guided by a cross member 21 for exerting pull in the proper direction when the loop 28 is lifted by means of hoisting apparatus.

The pinion I9 with its arms 23 are substantially the equivalent of a lever pivoted at I8 and operative on the rack rod and will be referred to as such in the broader definition of the invention.

In operation, assuming that the lifting device is suspended from a hoist by means of the cable 26, the hoist is rst operated to bring the bar opposite one of the open spaces within the pallet, whereupon the bar is pushed into the space until the vertical arms I3 of the lever reach the edge of the pallet. A slight upward pull on the cable will bring the upper faces of the bar and the horizontal lever legs into contact with the bottom face of the upper layer of planks.

On continuation of the upward pull, as the lifting device takes over the load, the arm 23 and the pinion I9, operating on the link 8, exert downward pressure on the latter which, in turn, forces the outer end of the bar 5 downward and urges the inner end of the bar upward into lifting contact with the pallet planks throughout the length of the bar.

At the same time the upward pull on the arm 23 urges the pivot I8 outward toward the link tending to urge the upright lever leg I3 toward outward slanting position and opposing any tendency of the leg i3 to swing toward inwardly inclined position as it naturally would if upward pull were exerted directly on the upright leg I3, in the absence of my lever mechanism 9.

The resulting eect to the lifting operation is 1 that both the horizontal lever legs l2 of the bell crank lever and the inner end of the bar 5 retain their horizontal positions throughout the lifting operation.

If the lifting devices are employed in opposing pairs so as to maintain the pallet in level position, the bars 5 will retain lifting contact with the upper layer of planks throughout the lengths thereof, and any danger of slipping is eliminated.

It should be noted that the entire lever mechanism 9 is arranged outside of the upright legs I3 so that no part thereof infringes on the vertical space above the pallet. The lever mechanism 9 is preferably arranged to make the lever arm 23 about twice as long as the radius of the pinion to cause the cable to work at a favorable leverage in urging the outer end of the bar 5 downward.

While my invention has been particularly described for use in connection with a pallet, it is apparent that it may be used in connection with the lifting of any load or platform having similar characteristics.

I claim:

l. A lifting device for a platform, comprising an anchoring means having a horizontal leg adapted for introduction underneath the platform, a bar pivoted in the anchoring means so as to extend inwardly underneath the platform, and means for lifting the anchoring means including means responsive to the lifting effort for urging the inner end of the bar upwardly into lifting contact with the platform, the inner end of the bar projecting inwardly beyond the horizontal leg.

2. A lifting device for a platform, comprising an anchoring means having a horizontal leg adapted for introduction underneath the platform, a bar pivoted in the anchoring means so as to extend inwardly underneath the platform, and means for lifting the anchoring means including a lever pivoted in the anchoring means and means operable by one end of the lever for urging the inner end of the bar upwardly into lifting contact with the platform when the other end of the lever is lifted.

3. A lifting device for a platform, comprising an anchoring means having a horizontal leg adapted for introduction underneath the platform, a bar pivoted in the anchoring means and having one end projecting inwardly underneath the platform and a second end projecting outwardly beyond the platform, and means for lifting the anchoring means including a lever pivoted in the anchoring means and means operable by one end of the lever for depressing the outer end of the bar when the other end of the lever is lifted whereby the inner end of the bar is forced into lifting contact with the platform.

4. A lifting devce for a platform, comprising an anchoring means having a horizontal leg adapted for introduction underneath the platform, a bar pivoted in the anchoring means and having one end projecting inwardly underneath the platform and a second end projecting outwardly beyond the platform, and means for lifting the anchoring means including a lever pivoted in the anchoring means and means operable by one end of the lever for depressing the outer end of the bar when the other end of the lever is lifted whereby the inner end of the bar is forced into lifting contact with the platform, the inner end of the bar projecting inwardly beyond the horizontal leg.

5. A lifting device for a platform, comprising an anchoring means having a horizontal leg adapted for introduction underneath the platform, a bar pivoted in the anchoring means and having one end projecting inwardly underneath the platform and a second end projecting outwardly beyond the platform, and means for lifting the anchoring means including a lever pivoted in the anchoring means and a link pivoted in the outer end of the bar and operable by the lever for depressing the outer end of the bar when one end of the lever is lifted whereby the inner end of the bar is urged into lifting contact with the platform.

6. A lifting device for a platform, comprising an anchoring means having a horizontal leg adapted for introduction underneath the platform, a bar pivoted in the anchoring means so as to extend inwardly underneath the platform, and means for lifting the anchoring means including means responsive to the lifting effort for urging the inner end of the bar upwardly into lifting contact with the platform, the horizontal leg of the anchoring means and the bar having cooperative means for limiting relative movement between the same.

7. A lifting device for a platform, comprising an anchoring means having a horizontal leg adapted for introduction underneath the platform, a bar pivoted in the anchoring means and having one end projecting inwardly underneath the platform and a second end projecting outwardly beyond the platform, and means for lifting the anchoring means including a lever pivoted in the anchoring means and means operable by one end of the lever for depressing the outer end of the bar when the other end of the lever is lifted whereby the inner end of the bar is forced into lifting contact with the platform, the horizontal leg of the anchoring means and the bar having cooperative means for limiting relative movement between the same.

8. A lifting device for a platform, comprising an elbow having a horizontal leg adapted for introduction underneath the platform and having a vertical leg adapted for pushing up against the edge of the platform, a bar pivoted to the elbow and having an inner end substantially paralleling the horizontal leg and an outer end projecting outwardly beyond the vertical leg, a lever supported by the vertical leg, and a link connection between one end of the lever and the outer end of the bar, whereby the outer end of the bar is pressed downward for lifting the inner end thereof when upward pull is exerted on the other end of the lever.

9. A lifting device for a platform, comprising an elbow having a horizontal leg adapted for introduction underneath the platform and having a vertical leg adapted for pushing up against the edge of the platform, a bar pivoted to the elbow and having an inner end substantially paralleling the horizontal leg and an outer end projecting outwardly beyond the vertical leg, a lever supported by the vertical leg, and a link connection between one end of the lever and the outer end of the bar, whereby the outer end of the bar is pressed downward for lifting the inner end thereof when upward pull is exerted on the other end of the lever, the lever being supported with respect to the vertical leg so as to leave the space above the platform unobstructed.

l0. A lifting device for a platform, comprising an elbow having a horizontal leg adapted for introduction underneath the platform and having a vertical leg adapted for pushing up against the edge of the platform, a bar pivoted to the elbow and having an inner end substantially paralleling the horizontal leg and an outer end projecting outwardly beyond the vertical leg, a lever supported by the vertical leg, and a link connection between one end of the lever and the outer end of the bar, whereby the outer end of the bar is pressed downward for lifting the inner end thereof when upward pull is exerted on the other end of the lever, the link connection comprising a link pivoted to the outer end of the bar and having a rack thereon, a pinion on the end of the lever, and spring means urging the rack upon the pinion.

11. A lifting device for a platform, comprising an elbow having a horizontal leg adapted for introduction underneath the platform and having a vertical leg adapted for pushing up against the edge of the platform, a bar pivoted to the elbow and having an inner end substantially paralleling the horizontal leg and an outer end projecting outwardly beyond the vertical leg, a lever supported by the vertical leg, and a link connection between one end of the lever and the outer end of the bar, whereby the outer end of the bar is pressed downward for lifting the inner end thereof when upward pull is exerted on the other end of the lever, the link connection comprising a link pivoted to the outer end of the bar and having a rack thereon, a pinion on the end of the lever, and spring means urging the rack upon the pinion, and the lever being supported with respect to the vertical leg so as to leave the space above the platform unobstructed.

HOWARD MADSEN.

REFERENCESV CITED UNITED STATES PATENTSJl Name Date Lull Feb. 5, 1946 Number 

